Incandescent gas fires



A. F. OATLEY INCANDESCENT GAS FIRES July 12, 1.966

4 Sheets-Sheet 1 Filed Feb. L3, 1964 July l2, 1966 Filed Feb. 6, 1964 A. F. OATLEY I NCANDESCENT GAS FIRES 4 Sheets-Sheet 2 Vvvvvvvwv l l ,lll

July 12, 1966 A. F. OATLEY 3,260,255

INCANDESCENT GAS FIRES Filed Feb. 6, 1964 4 Sheets-Sheet 5 July 12, 1966 A. F. OATLEY 3,260,255

INCANDESCENT GAS FIRES Filed Feb. G, 1964 4 Sheets-Sheet 4 to room exchanger unit.

United States Patent O M This invention relates to radiant-convector gas-fired, room heaters which incorporate in their construction a convector heat-to-room exchanger unit where heat is derived from the passage of the hot products of combustion through the heat exchanger unit to the chimney flue.

When a room heater of this type is installed, for example, in a fireplace opening and thereby forms a closure plate and the controlled entrance to the chimney flue through which pass the hot products of combustion from the fire, it is also subject, according to constructional shape, height, size and geographical location of the chimney, to the concentration of excessive chimney pull created by atmospheric lift and therefore inducts, at excessive speed and volume, cold room air from room to chimney flue.

The effect of cold air being drawn over the top of the gas fire radiants and through the passage or passages through which also traverse the hot products of combustion from the room heater through the heat exchange convector unit to the chimney flue is functionally diametrically opposed insofar that, Whereas the purpose of the heat to room exchanger unit is that of exchanging heat from the hot products of combustion to the room, cold room air inducted at excessive speed and volume diluting the hot products of combustion considerably reduces them in temperature thereby detracting from the effectiveness and efficiency of the heat exchanger under actual working conditions.

While, because of this, it is common practice to provide chimney breaks in a fireplace in order to minimize the concentration of excessive chimney pull through the room heater, such practice is only partly effective in that chimney pull is reduced only according to the size and release afforded by the chimney break. This, with variant factors of atmospheric lift, renders it a measurably unscientific practice and, in the case of a bad pulling chimney combined with a static atmospheric condition, could create a condition where, because of insufficient pull, the products of combustion from the fire would be emitted into the room instead of the chimney. Another common practice is that of fitting flue-pull restrictors, fixed or mechanical, to either the chimney flue or that of the room heater or both in order to slow down and reduce the passage of cold air from the room through the appliance to the chimney flue. Here again, because of constant variant unknown factors affecting chimney pull from atmospheric static condition to strong atmospheric lift, it is impossible to assess with any degree of accuracy the size or type of restrictor needed to effectively and safety minimize the cooling effect of chimney pull.

In both the foregoing practices, the purpose is to increase heat exchange to room by decreasing heat loss to chimney flue created by strong chimney pull. This is of the greatest importance where the re flue passage to chimney liuc is also functionally the convector heat In such radiant-convector fires the passage or heat exchanger which conveys the hot products of combustion to the chimney ue is the same passage which passes chimney pull inducted room air through the appliance which, in thecase of one type of radiant-convector fire, has a cooling effect on the radiants and, in another type, has an excessive cooling effect on 3,260,255 Patented July 124, 1966 ICC both the radiants and, by dilution of the hot gases, a so drastic cooling effect on the heat exchanger which, under low temperature conditions, could function in reverse becoming a heat exchanger from fire to chimney flue instead of that for which it is designed, a heat exchanger from heater to room.

The purpose of this invention is to provide a functional principle which will divert chimney pull inducted cold room air from passing through the passage or ducts traversed by the hot products of combustion through a heat exchanger and thereby prevent their drastic reduction in temperature by dilution caused by inducted cold room air. This is achieved by providing a separate and direct entry through the room heater to chimney flue which will functionally short-circuit inducted room air direct to chimney flue and thereby prevent it from the traversing of the passage taken by the hot products of combustion through the heat exchanger to chimney flue.

It is an object of the present invention to provide a radiant convector gas-fired, room heater having a flue ducted vent or Vents constructionally designed and so positioned as to short-circuit through the fire and thereby divert atmospheric lift inducted cold room air from traversing the same passage or ducts as that taken by the hot products of combustion passing through a convector heat-to-room exchanger unit on their way to the chimney flue.

It is a further object of the invention to provide a radiant convector gas-fired room heater comprising a chamber for receiving products of combustion rising from the radiant panel, a vent from the chamber adapted to open into a flue, direct access to the veut for air to be drawn from the room or other space being heated and means for inhibiting mixing of this air and the products of combustion except in the vent.

A still further object of the invention is to provide a radiant convector gas-fired, room heater comprising, above the radiant panel, a chamber toreceive the products of combustion which rise from the radiant panel, a substantially upright longitudinal baflfe dividing the chamber into front and rear parts and shaped to direct the rising products to the rear part of the chamber before they pass to the front part of the chamber, means of access for air direct from in front of the fire to the front part of the chamber and a vent or vents open to the front part of the chamber and passing rearwards through, but closed from the rear part for 4discharge at the back of the room heater of products and air to a flue.

The baille may be shaped to direct the products behind it by having along its lower edge an apron portion inclined forwards and downwards forming a hood to gather the products. This apron portion leaves a rwide opening for the direct access of room air to the front part of the chamber.

As the rear part of the chamber receives hot products of combustion almost undiluted by cool room air the temperature of the rear part of the chamber is high and it is ywell suited to .form a part of a heat exchanger. The rear wall of the chamber, which is particularly well heated by the flow of hot products over it, may for example, form part of the front wall of a convector passage which discharges Warm air to the room through an outlet at the upper part of the room heater. The air flowing through the convector passage may also be heated by an airheater behind the radiant panel.

If the vent or vents pass through the convector passage they may be thoroughly insulated from it, for exam-ple, by a double wall construction with an intervening air space, as the products and diluting cool air at this point may well be cooler than air flowing through the convector passage after heating in an air-heater. Alternatively, if the air in the convector passage had not been previously -warmed there would be a risk of condensation inside the vent.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which,

FIGURE 1 is a perspective view of the upper portion of a gas-tired room heater being partly broken away to reveal constructional details of the interior.

FIGURE 2 is a vertical section through the gas-tired, room heater.

FIGURES 3 and 4 are vertical sections of the upper portions of two alternative forms of gas-red room heater according to the present invention.

FIGURE 5 is a horizontal section through the gasred room heater taken on the line X-X of FIGURE 2.

The gas-tired, room heater illustrated in FIGURES 1, 2 and 5 of the accompanying drawings comprises a body including a sheet metal outer casing 5 and a cast metal main frame mem-ber 6 mounted in the casing 5; refractory radiants 7 forming a radiant panel at the front of the casing and being supported by a carrier 60 above a gas burner tube 8 having upwardly directed gas jets 9 along its lengths which project through openings 61 in the carrier 60 into the bottom of the radiants 7; and a heat exchanger chamber 10 in the upper portion of the casing above the radiant panel to receive the products of combustion which rise from the radiant panel.

The main frame member 6 has an upright wall portion 11 wku'ch is disposed substantially mid-way between the front of the casing S and a sheet metal back panel 12 of the casing and extends parallel to the back panel across the width of the casing. The space between the upright wall portion 11 and the back panel 12 forms part of a -convector passage 13 which extends from below the burner tube 8 behind the wall portion 11 and over the chamber 10. Air from the room in which the room heater is installed enters the convector passage 13 at an inlet `grille 14 in the lower end of the casing front and after leaving a convection air heater 17, behind the radiants 7 is deected forwards over the heat exchanger chamber 10 by a deilector 4 to an outlet grille 15 in the upper end of the casing front and hence back into the room. The air reaching the outlet grille 15 receives heat from the heat-exchanger chamber 10.

Combustion supporting air for the gas jets 9 of the gas `burner tube 8 is drawn from the air entering into the room heater through the inlet grille 14 and reaches the gas jets 9 by way of the apertures 61 in the carrier 60.

The upright wall portion 11 of the frame member 6 has an opening 16 corresponding substantially in shape to and slightly larger in area than the combined surface areas of the `backs 62 of the radiants 7. The radiants 7 are supported by the carrier 60 so that their backs 62 are disposed in the opening 16. On the rear surface of the wall portion 11 the convection air heater 17 is mounted, a cast front wall 18 lof which lies close against the rear surface of the wall portion 11 and extends behind the opening 16. The backs 62 of the radiants, which as stated are disposed in the opening 16, rest against the front wall 18 of the air heater and thereby heat the air heater 17. The air heater heats the air passing through the iconvector passage 13.

The air heater 17 is in the form of an upright narrow rectangular box which is open at the top and bottom and is divided internally by a corrugated partition 63 into vertically extending air ducts 64 as shown in FIG- URE 5, which are also open at the top and bottom.

The chamber 10 has a cast metal rear wall 19 which extends across substantially the width of the casing and is arranged so that it extends upwards from the upright wall portion 11 so that in effect it forms a continuation of the upright wall portion. The upper edge of the rear wall 19 is curved forwards and meets a sheet metal panel 20 which continues forwards and then downwards to form a lining spaced behind a front canopy casting 21 of the room heater above the level of the radiants 7. The lining panel 20 is secured near its upper edge to the rear wall 19 by screws, not shown, which screw into threaded bosses 22 cast integrally with the rear wall.

In the rear wall 19 two horizontally spaced openings 23 are formed leading to slightly tapered tubular vent housing 24 cast integrally with the rear wall and extending rearwardsacross the convector passage 13. Around each opening 23, integral with the rear wall and extending forwards from the front surface of the rear wall, is a short tubular spigot 25. The tubular spigot 25 is spaced slightly from the edge of the opening 23 so that there is a narrow annular land 26 around the opening.

The chamber 10 is divided into front and rear parts 27 and 28 respectively by a sheet metal baffle 29. For the greater part the baffle 29 is upright and flat. The 'baille 29 stops short of the top of the chamber and its upper edge 56 is inclined forwards. Opposite each spigot 25 the flat upright portion of the baille is pressed out rearwards to `form a circular rebated portion 30 which extends into the mouth of the tubular spigot 25. A vent opening 31 is formed in the rebated portion in register with the opening 23. The forward end of the spigot abuts the rear surface of the bafe around the rebated portion 3u.

Inside each vent housing 24 but separated from the vent housing so as to leave an air space 31 is a sheet metal vent tube 33 having a peripheral terminal flange 34 `which engages the narrow land 26 and locates the vent tube 33 in spaced relationship to the housing. The flange 34 is clamped against the narrow land 26 by the rebated portion 3i) of the baie 29. An annular sealing ring 35 is interposed between the rebated portion around the vent opening 31 and the flanges 34. The vent tube 33 extends rearwards, tapering complementarily to the housing, and opens to the back of the room heater through an aperture 36 in the back panel 12. A hood 37 of semicir-cular shape is secured to the back panel around the edge of the upper half of the aperture 36 and extends rearwards into the chimney flue 55 indicated in broken lines in FIG-URE 2. The baffle 29 is secured to the rear wall 19 by screws 3S which screw into internally threaded bosses 39 cast integrally with `the rear wall.

Below the vent openings 31 the lower portion of the baille 29 is inclined forwards and downwards to form an apron 40 which overhangs the front of the radiants with its lower horizontal edge at about the level of the top of the radiants so that it forms a hood to gather the products of combustion rising from the radiants and directs them into the rear part 28 lof the chamber 10.

The front canopy casting 21 and the lining panel 29 at their lower parts are parallel to the apron 4t) but well spaced away leaving a wide upwardly and inwardly directed passage 41 for room air to reach the front part 27 of the chamber and the vent openings 31. A cast metal cowl 42 is secured to the lower end of the lining panel whose lower edge projects below and forwards of the bottom edge of the canopy 21. This cowl 42 serves to direct the room air mainly to the chamber although some air may pass between the canopy and lining panel upwards to the outlet grille 1S.

Products rising from the radiants are gathered, as previously stated, by the apron 40 into the rear part of the chamber 10, flow up around the tubular spigots 2S, down the front face of the baille 29 and into the vent openings 31 and thence pass through the vent tubes 33 to the chimney flue 55. The products Warm up the baffle and vents `tubes quickly when the room heater is lighted and air flow commences through the vent tubes by convection before the chimney flue has warmed enough to `exert a pull. It is usually found with gas-fired, room heaters that, until the chimney has warmed, a little of the products escape into the room. In this respect the above described construction shows an improvement since it has been found that products are cleared at an appreciably lower chimney pull than normal.

The convector passage is sealed from the chamber so that there is no possibility of the air passing through the passage and being heated by the air heater or mixing with the products of combustion.

The air space 32 left between the vent housing and vent tubes thoroughly insulates the vents from the convector passage. This insulation is an important feature because the products and diluting cool air from the room may well be cooler than the heated convection air ilowing through the convector passage and thus without insulation would cool the convection air. Also if the air in the convector passage had not been previously warmed there would be a risk of condensation inside the vent tubes.

Since the rear wall of the chamber 10 is heated by the products of combustion it also imparts heat to the convector passage 13.

In the alternative arrangement shown in FIGURE 3 the room heater construction is generally similar to that just described except that a tapered tube 44 is provided which extends rearwards from a grille aperture 45 in the canopy casting 21. In this arrangement the rear Wall 19 has no vent housing 24 or tubular spigot 25 and there is no baille 29 provided in the chamber 10. The tapered tube 44 is made of sheet metal, its mouth being in register with the grille aperture 45 in the canopy, and it extends rearwards and diverges slightly towards its rear end. The tube 44 extends through the lining panel 20, across the chamber 10, through the opening 23 in the rear wall 19` Iof the chamber and extends a short way beyond the rear wall. Around the rear part of the tube 44 there is a sheet metal tubular ilue connection 47. which is of such diameter that there is a space between it and the outer surface of the tube 44. The mouth of the flue connection 47 is open and disposed in the chamber 10. The ilue connection 47 extends rearwards through the opening 23 and across the convector passage 13 and out through the back panel 12 of the room heater to the chimney flue 55. Beyond the rear end of the tube 44, the flue connection 47 converges to form a vent 46 having a throat 48 and said vent 46 diverges slightly in a short venturi-shaped section 49 just before it opens into the flue. The common axis of the tube 44 and ilue connection 47 is slightly inclined upwardly from front to back.

Products rising from the radiants 7 ilow into the open mouth of the flue connection 47 in the chamber 10. When the room heater is lighted, the part of the tube 44 exposed inside the chamber warms up quickly and, because of the inclination of the tube 44, air ilow cornmences through the tube by convection before the ilue 55 has warmed enough to exert a pull. The discharge of `this air ilow into the venturi section 49 of the vent 46 has an inspirating effect and draws the products collecting in the chamber 10 out into the ilue. This minimises the tendency, which may at first exist, for some of the products to pass out into the room.

As the llue connection 47 surrounds most of the tube 44 and hot products ilow through theA annular space between the tube and the ilue connection the tube is largely insulated so that, even though it passes through the room heater it does not cause excessive loss of heat.

The arrangement shown in FIGURE 4 also has a tube 50 which extends from a grille aperture 51 in the canopy 21. This tube 50 is of constant cross-section, and extends rearwards through the lining panel across the chamber 10, through the opening 23 in the rear wall 19 of the chamber and continues right across the convector passage 13 to an aperture 52 in the back panel 12. The rear portion 65 of the tube 50 constitutes a vent. In this arrangement a baille 53 is provided which divides the chamber space into front and rear parts 66 and 67 respectively but unlike the baille of the iirst described embodiment it is shaped at its lower end so as to direct the products rising from the radiants '7 to the front part 66 of the chamber. The products rise up the front part 66 of the chamber around the tube 50 then over the upper edge of the baille 53 and downwards behind the baille into the rear part 67` of the chamber. In the portion of the tube 50 between the baille 53 and rear wall 19, apertures 54 are formed through which the products having reached the rear part 67 of the chamber 10 pass into the vent portion 65 of the tube 50 and thence, with the room air ilowing through the tube, into the ilue passage.

I claim:

1. A radiant and convector gas-red, room heater comprising in combination a body; a gas-heated radiant panel at the front of the body; at least one vent adapted to be connected to a draught-inducing flue; a heatexchanger having separated paths in thermal transferring relationship for products of combustion and for convection air, the products path having an entry disposed to receive products from the radiant panel and an exit open to the vent, and the convection air path having an outlet from the body; means for admitting inducted air through the room heater to the Vent and means for diverting such inducted air from the products path and directly into the vent.

2. A radiant and convector gas-fired, room heater comprising in combination a body; an open gas-heated radiant panel at the front of the body; walls in the body dening a chamber having an open bottom above the radiant panel to receive products of combustion rising therefrom; at least one vent from the chamber adapted to be connected to a draught-inducing flue and open directly to the open front of the radiant panel for air admission and means for inhibiting mixing of the air and the products of combustion except in the vent.

3. A radiant and convector gas-tired, room heater comprising in combination a body; a gas-heated radiant panel at lthe front of the body; structure defining a chamber in the body and an opening over the radiant panel to receive products of combustion therefrom; a substantially upright baille dividing the chamber into front and rear parts and shaped to direct the rising products to the rear part of the cham-ber before they pass to the front part of the chamber, means of access for air direct from in front of the room heater to the front part of the chamber and at least one vent open to the front part of the chamber and passing rearwards through, but closed from, the rear part and open at the back of the room heater for connection to a flue.

4. A radiant and convector gas-tired, room heater according to claim 3 wherein the baille has along its lower edge an apron portion inclined forwards and downwards forming a hood to gather the products.

5. A radiant and convector gas-fired, room heater according to claim 3 wherein there is a gap between the upper edge of the baille and the top wall of the chamber through which products can pass from the rear to the front parts of the chamber.

6. A radiant and convector gas-fired, room heater according to claims 3 wherein the chamber heats convector passages in the room heater.

7. A radiant and convector gas-tired, room heater according to claim 3 wherein the vent passes through a convector passage and the portion 'within the passage is thermally insulated.

References Cited by the Examiner UNITED STATES PATENTS 1,855,980 4/1932 Merrill 126-92 FREDERICK L. MATTESON, IR., Primary Examiner.

ROBERT A. DUA, Assistant Examiner. 

1. A RADIANT AND CONVECTOR GAS-FIRED, ROOM HEATER COMPRISING IN COMBINATION A BODY; A GAS-HEATED RADIANT PANEL AT THE FRONT OF THE BODY; AT LEAST ONE VENT ADAPTED TO BE CONNECTED TO THE DRAUGHT-INDUCING FLUE; A HEATEXCHANGER HAVING SEPARATED PATHS IN THERMAL TRANSFERRING RELATIONSHIP FOR PRODUCTS OF COMBUSTION AND FOR CONVECTION AIR, THE PRODUCTS PATH HAVING AN ENTRY DISPOSED TO RECEIVE PRODUCTS FROM THE RADIANT PANEL AND AN EXIT OPEN TO THE VENT, AND THE CONVECTION AIR PATH HAVING AN OUTLET FROM THE BODY; MEANS FOR ADMITTING INDUCTED AIR THROUGH THE ROOM HEATER TO THE VENT AND MEANS FOR DIVERTING SUCH INDUCTED AIR FROM THE PRODUCTS PATH AND DIRECTLY INTO THE VENT. 